Safety joint



July 28, 1936. E. BURNS ET AL SAFETY JOINT I Filed April 7. 1935 2 Sheets-Sheet 1 July 28, 1 936. E BURNS ET AL 2 ,049,289

SAFETY JOINT Filed April '7, 1955 2 Sheets-Sheet 2 @2 l? Patented July 28, i936 UNITED STATES PATENT OFFICE sham, Huntington Park, Calif., one-third to LawrenceF.

' cam.

assignors of Baash, Los Angelea,

Application April '1, 1933, Serial No. 664,900

'iClaims.

This invention relates to a-releasable coupling or connection, and relates more particularly to a safety joint. It'is a general object of the present invention to provide a simple, practical and dependable safety joint for use in a rotary drilling 1 string.

In the rotary method of well drilling, the drilling tool is operated on the lowerend of a drilling string made up of lengths of pipe connected by threaded couplings and tool joints. The drilling tool quite frequently becomes caught in the well so that it cannot be withdrawn. when this occurs it is desirable to disconnect the drilling string or the major portion of the drilling string from the tool and remove it from the well so that the tool may be accessible for fishing operations, etc. In order to provide for disconnection of the drilling string or the greater portion of the drilling string from the tool, a safety joint is interposed in the lower portion of the string that is capable of being disconnected if itbecomes desirable or necessary to disengage or separate the drilling string from the tool. A practical and succesful safety joint must be capable of dependably and positively transmitting heavy tensile and compression strains, and torsional or rotation strains in one direction, and be adapted to'be disconnected by simple manipulation of the drilling string that will not break or disconnect any of the other joints or connections in the string.

It is an object of this invention to provide a safety joint that normally forms a strong dependable and positive connection, and that may be easily and quickly released by turning the drilling string in a reverse or left hand direction.

It is another object of the invention to provide a safety joint that is adapted to dependably and positively transmit any compression, tensile or right hand torsional strains to which the drillin string may be subjected.

It is another object of the invention to provide a safety joint that cannot become jammed or locked against easy disconnection.

It is another object of the invention to provide a safety joint of the character mentioned having an improved and simplified construction and arrangement of parts.

It is another object of the invention to provide asafety joint of the character mentioned that includes two threadedly connected sections or members and a spring pressed sleeve slidable but nonrotatable on one member and having a lug and notch connection with the other member that transmits torsional strains between the members in one direction and that is releasable against the action of the spring by torsional strain in the other direction.

It is another object of the invention to provide a safety joint of the character mentioned involving a novel and eflective means for locking or retaining the slidable sleeve on one of the body members.

It is a further object of the invention to provide a safety joint of the character mentioned that is operable to transmit rotary or torsional strains in a right hand direction after being partially released or disconnected.

Further objects and features of the invention will be better and fully understood from the following detailed description of typical forms and applications of the invention, throughout which description reference is had to the accompanying drawings, in which:

Fig. 1 is a side elevation of one embodiment of the invention. Fig. 2 is a longitudinal detailed sectional view of the joint illustrated in Fig. 1 showing the parts in partially released positions. Figs. 3 and 5 are enlarged transverse detailedsectional views taken as indicated by lines 3-3 and 5-5 respectively on Fig. 2. Fig. 4 is an enlarged transverse detailed sectional view taken as indicated by line 4-4 on Fig. 8. Fig. 6 is a side elevationof another form of the invention illustrating the sleeve or ring in partial engagement with the lower body member. Fig. 'l is a view similar to Fig. 6 illustrating the manner of disconnecting the lugs from the notches to permit the parts to be fully connected, and Fig. 8 is a longitudinal detailed sectional view of the safety joint illustrated in Figs. 6 and 7 showing the parts in a fully connected position, and illustrating the upper body section in elevation.

The form of my invention illustrated inFigs. l, 2, 3, and 5 of the drawings, includes, generally, two body sections or membersA and B'having a releasably screw threaded connection C, a sleeve or ring III shiftable longitudinally on the member A and having a releasable connection with the member B limiting relative rotation between the members A and B in one direction, and means ll yieldingly holding the ring In in its operative position in cooperation with the member B.

The body sections or members A and B constitute a separable assembly adapted to be interposed in an operating string or drilling string of drill pipe, or the like. The member A which will be termed the upper member is adapted to be connected with the upper or major portion of the drilling string, being provided at its upper end with means for connecting with the The leasably threaded connection the socket l8. Packing 62 is arranged in an an I and is adapted bers A a The sleeve or ring l0 surrounds the upper member A may be sectional and may include a stem I1 and a connecting member or sub 60 on the upper end of the stem. The stem II! is threaded into the lower end ofthe sub 60 and the sub is provided at its upper end with a tapered screw threaded socket l2 for receiving a. pin 9 of a connecting member on the string. The lower member B is provided at its lower end with a projecting pin l3 which is adapted to be screw threaded into a socket I 4 in a drill collar or connecting part in the drilling string. While we have illustrated the device disposed so that the upper member and the member A and B are tubular, having aligned longitudinal fluid passages l5 and I6, respectively. 7

The releasable threaded connection 0 between the members A and B'includes a thread on the stem of the male or upper member A adapted to cooperate lower'memberB. The threads 19' on and the walls of the socket l8 are preferably com paratively'heavy and have a substantial pitch.

socket by left-handor counter clock-wise rotation of the member A relative to the The socket stem I1 is of considerable length solthat theore- C between the number of turns are required to unscrew the" parts.

nular groove 64 inthe portion 6! to seal with the wall of the soc to d B.

wardly facing shoulder 22 onthe stem II to limit the downward'movement of the ring on the member A and to prevent the displacement of the ring A from the body member. a

A lug and notch connection between the ring l0 and the body mem er B prevents turning or the member A relative to' the member B after the stem I! has been threaded a pre-determined dis with notches ly facing shoulders 28 extending with a thread in a socket |8 in the the'stem l1 tudinal axis member LB. I8 is comparatively deep and the tance into the socket I8- cannot become jammed and so that right hand rotational or torsional strains are transmitted from the body member A to the body member B independently of the threads l9. The disengageable bearing or thrust connection between the ring I 0 and the body member B includes one or more lugs 25 on the ring I07 for cooperating or recesses 26 in the upper end of the body member B. In the particular embodiment of the invention illustrated in the drawings, there are two diametrically opposite lugs 25 for cooperating with two correspondingly shaped recesses 26 in the upper end of the body member B. e forward ends 21 of the lugs 25, relative to 'the right hand direction of rotation,

are flat and extend downwardly and slightly for wardly from the lower end of'the ring Ill. The forward ends of the'recesses 26 present rearwardupwardly and slightly rearwardly to the upper end of the member B. The rear ends of the lugs 25 and walls of the recesses 26 are inclined body member B are flat and normal to the longiof the joint and are adapted to cooperate with one another when the parts are in the positions illustrated in Fig. 1 of the drawings.

The lugs 25 and the recesses 26 are proportioned and related so that the lugs 25 are fully received in the recesses when the ring In is m ber B.

The means ll yieldlngly holds the ring in down in engagement with the upper end of the body member B so that the lugs 25 are maintained in cooperation with the recesses 26. The means If ring In on the During the member A.

so that the threads I9- cooperate'withthe member members A and B transmits tensile and compression strains between the sections. In the event that it becomes desirable or necessary to disconnect the joint when it is interposed in a drilling string in a well bore, the string is turned in a counter-clockwise or left hand direction so that the member A and ring H! are turned in a left hand direction relative to the member B. Turning of the body member A in a left hand direction relative to the member B causes the inclined rear ends of the lugs 25 to ride out of the recesses 25. Continued turning of the member A in a left hand direction unthreads the stem 61 from the socket I8. During unthreading of the stem from the socket the threads move upwardly relative to the member B so that the lugs 25 ,are shifted out of engagement with the member B. The shoulder 22 holds the ring l0 against'downward movement in a position where it is fully out of engagement with the memberturned approxileft hand direc- B when the member A has been mately one half revolution in a tion.

The threads i9 cannot become jammed or locked together as the ring It in cooperating with the member B, positively limits threading together of the members ease with which the stem ii may be unthreaded from the socket it, the joint may be disconnected with the upper end of the member F to prevent further threading together of the members A and B and to transmit right hand or clockwise torsional strains between the two members. The lower end of the ring 40 is spiralled or provided with two helicoidal faces terminating at their opposite ends in downwardly projecting lugs 44.

The upper end of the body member F is provided with two pitched or spiralled faces which l9 cause the member A to I A and B. Due to the without danger of breaking or loosening any of the other connections in the drilling string. The spring it normally operates to retain the ring it in the position where the lugs 25 are in fullv mesh or cooperation with the recesses 26 where they positively prevent further threading together of the members A and B and dependably transmit the right hand rotational strains from the member A to the member B. The slight rearward inclination of the cooperating faces or shoulders 21 and 28 eliminates the possibility of the lugs 25 becoming accidentally or unintentionally disengaged from the recesses 26. The joint is extremely simple and inexpensive of manufacture, and is positive and dependable in operation.

In the embodiment of the invention illustrated in Figs. 4, 6, '7 and 8 of the drawings, the body members E and F are similar to the body members A and B. The upper body member E is adapted to be connected with the drilling string while the lower connected with the drilling tool. The member E is illustrated as being integral and the lower end portion of the member E is in the nature of a stem adapted to be threaded into a socket 36 in the member F. The threads 37 of the stem and socket are comparatively heavy and have a substantial pitch. Fluid pressure actuated packing at is provided in a groove in the stem 35 to seal with the wall of the socket 36 and to present leakage between the members E and F. A ring to surrounds the upper above the threaded stem 35 and is adapted to F to limit rotation of the member E, in a right hand direction relative to the member F. Splines or keys 4| on the ring 4i] and member E hold the ring against rotation on the member. The ring is adapted to shift or slide longitudinally on the member E and its downward movement is limited by a retaining ring 42. The ring 42 is in the nature of a split ring or spring arranged in an annular groove 10 I in the stem and adapted to be engaged by the I lower ends of the splines 4| of the ring 46. threaded a predetermined 36, the ring 40 cooperates When thestem 35 is distance into the socket body member F is adapted to be' member E at a point,

tion relative to the member F is then prevented terminate in downwardly extending recesses 45, shaped and proportioned to receive the lugs 44. Inaccordance with the invention, the spiralled lower end of the ring 40 and upper end of the member F are pitched in the same direction as the threads 31 and have the same inclination as the threads. The forward ends 46 of the lugs 44 and the forward ends 41 of the recesses are flat and extend longitudinally and slightly rearward relative to the right hand direction of rotation. The rear ends of the lugs 44 and the rear walls of the recesses 45 are inclined upwardly and rearwardly and are adapted to cooperate to allow the lugs to ride or slide out of the recesses when the member E is turnedin a left hand direction relative to the member F.

In the form of the invention being described, the recesses 45 are comparatively deep and the lugs M are comparatively long so that the shoulders 46 and 41 present substantial thrust or bearn surfaces. When the joint is fully made up,

ing the lugs 64 are completely received in the recesses 45 and the lower end of the ring 40 seats on the upper end of the member F. Means is provided for normally yieldingly-holding the ring 40 in its down position where the lugs 44 are in full mesh with the recesses 45. A spiralled spring 48 is arranged under compression between the upper end of the ring 40 and a downwardly facing shoulder 49 on the member E to normally maintain the lower end of the ring in engagement with the upper end of the member F.

In assembling the safety joint illustrated in Figs. 4, 6, and '7, of the drawings, the stem 35 is screw-threaded into the socket 36 by turning the member E in a right hand direction relative to the member F until the parts assume the positions illustrated in Fig. 6. When the parts are in this position, the forward ends 46 of the lugs engage the forward walls 47 of the recesses to prevent further turning of the member E in a move the forward faces 46 of the lugs out of cooperation with the forward ends 41 of the recesses. The upper member E may then be turned approximately one-half of a revolution to bring the lugs, 44 into full cooperation with the recesses 45 and the lower end of the ring- 40 in cooperation with upper endof the member F. Further rotation of the member E in a right hand direcso that the threads 31 on thestem and socket cannot become jammed 'or tightly set together. With the parts in the position where the lugs 44 are in full engagement with the recesses 45, right hand or clock-wise rotational strains are transmitted from the member E to the member F through the ring 40 and its lugs 44 which cooperate with the recesses 45.

To disconnect the member E from the member F, the member E is turned or rotated in a member F. When the member E has been rotated about one-half of a turn, the lugs 44, in being urged downwardly by the spring 481, snap or pass over the forward ends 41 of the recesses 45 so that the lugs assume the position illustrated in Fig. 6 of the drawings. As the forward ends 46 of the lugs are in cooperation with the forward ends 41 of the recesses when the parts are in this partially released position, clockwise or right hand rotation may be transmitted from the member E to the member F if this is found necessary or desirable. Further rotation of the member E in a left handdirection relative to the member F when the ring 40 is in the position illustrated in Fig. 6, fully disengages the ring 40 from the member ,F and complete disengagement of the member E from the member F may be had by unthreading the stem from the socket 36. The retaining ring 42 limits downward movement of the ring and the cooperation between the threads 31 during the disconnection of the joint causes upward movement of the member E relative to the member F so that the ring 40 is fully disengaged from the member F when the member E has been turned approximately one complete revolution in a left hand direction relative to the member F.

The safety joint illustrated in Figs. 4, 6, 7 and 8 of the drawings is particularly dependable and sturdy, as the lugs 44 are comparatively long and have large thrust surfaces 41 for cooperating with the forward ends 41 of the recesses to transmit right hand rotational strains from the mem ber E to the member F. The joint may be easily and quickly disconnected when desired or found necessary but is not subject to accidental or unintentional disconnection or failure. The lugs 44, in cooperating with the recesses positively prevent rotation of the member E in a right hand direction relative to the member when the joint is fully made up so that the threads 31 cannot become tightly set or jammed.

Having described only typical forms and appli cations of our invention, we do not wish to limit ourselves to the specific forms and applications herein described, but wish to reserve to ourselves any modifications or variations to those skilled in the art or fall of the following claims.

Having described our invention, we claim:

1. A safety joint including two sections, clutch parts on adjacent ends of said sections to limit within the scope relative rotation of the sections in one direction,-

a tubular member extending through one of the sections and into the other of said sections, a threaded connection between said tubular member and said last named section, a positive slidable connection between said tubular member and the section through which it extends, and means acting between a shoulder on the tubular member and the section through which it extends to hold the clutch means in tation in one direction and for yieldable releasing engagement for rotation in the opposite direction to completely unscrew the threaded connection by continuous rotation.

2. A safety joint'including two complementary that may appear positive engagement for no sections, clutch parts on adjacent ends of the sections adapted to cooperate to limit turning between the sections, a third section within the tubular complementary sections, a threaded connection between the third section and one of said complementarysections, a splined connection between the third section and the other of said complementary sections, packing on the third section forming a seal with the first mentioned complementary section, and expanding means acting between the third section and the second mentioned complementary section to control the disengagement of the clutch parts of the complementary sections. I

' 3..A safety joint including two complementary members, clutch shoulders formed on contiguous faces of said members, said shoulders abutting back faces whereby rotation in the opposite direction would cause relative longitudinal shifting of the complementary sections with relation to each other, a central tubular member splined to one of said complementary members andhaving a threaded connection with the other of said complementary members, yieldable means acting between the central member and the complementary member to which relative longitudinal movement between said members and for maintaining the shoulders of the complementary members in driving engagement when said central member is threaded into the other complementary members.

4. Asafety joint including two complementary members, clutch shoulders formed on contiguous faces of said members, said shoulders abutting against each other to prevent rotation in one direction and having complementary inclined back faces whereby rotation in 'the opposite direction would cause relative longitudinal shifting of the complementary sections with relation to each other, a central tubular member splined to one of said complementary members and having a threaded connection with the other of said complementary members, yieldable means acting between the central member and the complementary member to which it is splined for permitting relative longitudinal movement between said members and for maintaining the shoulders of the complementary members in driving engagement when said central member is threaded into the other complementary memher, and packing means between the central member and the complementary member into which it is threaded to produce a fluid seal therebetween.

'5. A safety joint including two tubular sections, clutch parts on adjacent ends of the sections adapted to limit relative turning of the sections, a third section releasably threaded into one of said sections and extending into the other of said sections, there being a fluid passage through the sections, means for sealing between the first mentioned section and the third section and means governing the release of the clutch parts normally holding the clutch parts in engagement and yieldable to permit disconnection of the clutch' parts after limited unthreading of thethird section from said other section by the application of an external torsion strain to said other section.

6. A safety joint including two tubular sections, clutch parts on adjacent ends of the sections adapted to coperate to limit relative tuming of t e sections, and releasable means holding it is splined for permittinging of the sections, and releasable means holding the sections against relative longitudinal movement, the said means including a third section threaded into one'of the said sections and having a key connection with the other of said sections, and shoulders on the third section and the said other section normally preventing longitudinal movement between the sections in one direction, the clutch parts being disengageable after limited unthreading of the third section and the said other section by the applica- 10 tion of an external torsion strain to said other section.

ERWIN BURNS.

HARRY P. WICKERSHAM. 

